This is not my fathers or my mothers physical chemistry course Michelle M' Francl Bryn Mawr College

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This is not my fathers (or my mothers) physical
chemistry courseMichelle M. Francl ? Bryn Mawr
College
The goal of this NSF funded project is to produce
a trial set of materials that can be used in
physical chemistry courses to more tightly
connect the topics introduced in available texts
to the realm of modern chemical research. These
curricular materials are intended to facilitate
the integration of context-rich teaching
strategies into the physical chemistry
curriculum. Materials are based on the primary
literature and include biographical, historical
and scientific background with the goal of
embedding physical chemistry concepts and skills
in the broader context of the discipline. This
project will foster the development of a robust
set of context-rich materials for physical
chemistry lecture that are more focused than case
study approaches, yet bring a richer and more
up-to-date perspective than either the text or
the problems in most texts can provide.
This material is based upon work supported by the
National Science Foundation under Grant No.
0340873. Any opinions, findings, and conclusions
or recommendations expressed in this material are
those of the author(s) and do not necessarily
reflect the views of the National Science
Foundation.
Which is from my fathers physical chemistry
book? Mine? The one written by my colleague who
retired in the 1920s?
Context Free Find an expression for the
half-life of the third-order reaction 3A ?
B. Contextualized The gas-phase formation of
phosgene, CO Cl2 ? COCl2 is 3/2 order with
respect to CO. Derive the integrated rate
equation for a 3/2 order reaction. Derive the
expression for the half-life. Context rich In a
paper by Bada, Protsch and Schroeder Nature 241,
394 (1973), the rate of isomerization of
isoleucine in fossilized bone is used as an
indication of the average temperature of the
sample since it was deposited. The
reaction L-isoleucine ? D-alloisoleucine iso
allo produces a nonbiological
amino acid, D-alloisoleucine, that can be
measured using an automatic amino acid analyzer.
At 200C, this first order reaction has a
half-life of 125,000 years and its activation
energy is 139.7 kJ mol-1. After a very long time,
the ratio allo/iso reaches an equilibrium value
of 1.38. You may assume that this equilibrium
constant is temperature independent. For a
hippopotamus mandible found near a warm spring in
South Africa, the allo/iso ration was found to be
0.42. Assuming that no allo was present
initially, calculate the ratio of the
concentration of allo now present to the
concentration of allo after a very long time
(Note the correct answer is between 0.40
and0.60). Radiocarbon dating, which is
temperature independent, indicated an age of
38,600 years for the hippo tooth.
Demographics Faculty N10 0-35 yrs teaching
physical chemistry 1/2 using Atkins
DePaula Institutions 1300-45,000
undergraduates 3-100 in physical chemistry course

• Available Materials
• Miniature Machines "Pulling" Nanowires Angew.
  Chem. Int. Ed. 2003, 42, 2251-2253
• Quantum Spheres Particle-on-a-sphere model for
  Buckminsterfullerene Chem. Phys. Lett. 1993,
  205, 200-206
• Frog Antibiotics Statistical Mechanics of
  Helix-Coil J. Mol. Bio. 1999, 294, 785-794
• Using Chemistry to Uncover a History Is this an
  early map of North America - or not? Anal. Chem.
  2002, 74, 3658-3661
• Exotic Kinetics Oscillating Reactions in the
  Atmosphere J. Phys. Chem. A 2001, 105,
  11212-11219
• Ancient Ostrich Eggs Dating materials by amino
  acid racemization Science 1990, 248, 60-64

• These are not
• to teach library or literature skills
• to replace texts
• to add new topics
• ThWhat they are
• They are
• To replace current examples with current
  materials
• Flexible
• Stand alone
• Extendable
• Context-rich

Faculty Assessment Positives choices of
papers, background, marginalia nd critical
reading problems Challenges difficulty of some
problems, more background, teaching notes
needed Comments The "cheetos" sidebar
stimulated a nice review of modeling conjugated
systems. I have been trying to impress upon my
students that PChem does have something to offer
biochemistry.The problems asked involve a model
(chosen perhaps because it was doable) that
doesn't fit the data. I think the students felt
deflated by that - although it does teach a good
lesson about the limitation of models.
Papers Short Current Readable Cross disciplinary

• Paper
• Background
• Marginalia
• Problems
• Additional Reading

Marginalia Context-rich materials embed specific
principles drawn from a curriculum into a web of
related information. These materials open up for
students the "who, what, when, where, and why?"
of a concept. There is good evidence that
context-rich curricula can attract and retain a
diverse group of students, engage students with a
wide variety of learning styles, as well as
improve student performance. The best
context-rich materials will offer concrete
examples, feature connectivity between
disciplines, introduce methodology, and
acknowledge the impact solving a problem can have
in the broader world.
Student Comments Archeometry Materials gt3/4
found paper interesting, readable, able to grasp
the main idea Problems are challenging, but
interesting More background Read marganalia and
are interested, but if prompted confess to being
distracted by it Additional reading? Not us!
Critical Qeading Questions In an early paper
describing this method Science, 1970, 170,
730-732, there is a note that at equilibrium a
small excess of D-alloisoleucine is present (at
140oC they report the ratio of alloisoleucine to
isoleucine is 1.25), but that for most amino
acids the equilibrium constant between the L and
D forms is 1. Why should that be? Why do you
suppose it is different for isoleucine?
Problems An early version of this method Bada
et al. Science, 1970,170, 730-732 ignored the
reverse reaction in computing the A/I ratio.
Derive an expression for the A/I ratio as a
function of time assuming you can ignore the
reverse reaction. A note in the early paper
suggests that this approximation is good until
the racemization exceeds 15. Compare your
expression with the one you derived in question
8. Do you agree with Bada et al.? How does the
approximation change the age range that can be
dated using this technique? Could the authors of
the paper on ostrich eggs have used the
approximate approach and still obtained accurate
dates? Support your answer with examples.
Where next? Also, I felt that I really needed to
fix up the questions to lead them through the
important points of the article. Finally, I
should state that I think they're an excellent
idea and an excellent resource. I just need to
work on implementation. Revise the questions
providing wider range, particularly in the
critical reading end of things. Solutions and
teaching notes need to be added.

• Further Reading
• Reliability of Amino Acid Racemization Dating
  and Paleotemperature Analysis on Bones, M. L.
  Bender, Nature, 1974, 252, 378-379. Dr. Bada
  Replies, J.L. Bada, ibid. 1974, 252, 379-381.
  An early controversy over the accuracy of the
  dates obtained from amino acid racemization.
• See the whole Chaucerian litany in either Middle
  English or Modern English at http//classiclit.abo
  ut.com/library/bl-etexts/gchaucer/bl-gchau-can-can
  -m.htm. Want the full medieval experience?
  Images of the full text of two 15th century
  versions can be found at http//www.bl.uk/treasure
  s/caxton/homepage.html. You can read the Canons
  Yeomans Tale in (almost) its original form
  thanks to the British Library.